As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR INTERRUPT, DURING CRUISE CREW REPORTS 1.5 HOURS INTO FLIGHT EICAS SHOWED, LOW QTY, WITH RT HYD SYS QTY .48 DISPLAYED THEN SLOWED TO APPROX .8 PER MIN AT .20 SHUT PUMPS OFF. REPLACED THE O RING ON RT ENG DRIVEN PUMP FILTER MODULE PRESS PORT IAW AMM 29-11-17. SERVICED RT HYD SYS. PERFORMED OPERATIONAL & LEAK CHECKS. SYS CHECKED NORMAL.